/*
 * Copyright (C) 1999 - 2010 Intel Corporation.
 * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
 *
 * This code was derived from the Intel e1000e Linux driver.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 */

#include "pch_gbe.h"
#include <linux/module.h>       /* for __MODULE_STRING */

#define OPTION_UNSET   -1
#define OPTION_DISABLED 0
#define OPTION_ENABLED  1

/**
 * TxDescriptors - Transmit Descriptor Count
 * @Valid Range:   PCH_GBE_MIN_TXD - PCH_GBE_MAX_TXD
 * @Default Value: PCH_GBE_DEFAULT_TXD
 */
static int TxDescriptors = OPTION_UNSET;
module_param(TxDescriptors, int, 0);
MODULE_PARM_DESC(TxDescriptors, "Number of transmit descriptors");

/**
 * RxDescriptors -Receive Descriptor Count
 * @Valid Range:   PCH_GBE_MIN_RXD - PCH_GBE_MAX_RXD
 * @Default Value: PCH_GBE_DEFAULT_RXD
 */
static int RxDescriptors = OPTION_UNSET;
module_param(RxDescriptors, int, 0);
MODULE_PARM_DESC(RxDescriptors, "Number of receive descriptors");

/**
 * Speed - User Specified Speed Override
 * @Valid Range: 0, 10, 100, 1000
 *   - 0:    auto-negotiate at all supported speeds
 *   - 10:   only link at 10 Mbps
 *   - 100:  only link at 100 Mbps
 *   - 1000: only link at 1000 Mbps
 * @Default Value: 0
 */
static int Speed = OPTION_UNSET;
module_param(Speed, int, 0);
MODULE_PARM_DESC(Speed, "Speed setting");

/**
 * Duplex - User Specified Duplex Override
 * @Valid Range: 0-2
 *   - 0:  auto-negotiate for duplex
 *   - 1:  only link at half duplex
 *   - 2:  only link at full duplex
 * @Default Value: 0
 */
static int Duplex = OPTION_UNSET;
module_param(Duplex, int, 0);
MODULE_PARM_DESC(Duplex, "Duplex setting");

#define HALF_DUPLEX 1
#define FULL_DUPLEX 2

/**
 * AutoNeg - Auto-negotiation Advertisement Override
 * @Valid Range: 0x01-0x0F, 0x20-0x2F
 *
 *       The AutoNeg value is a bit mask describing which speed and duplex
 *       combinations should be advertised during auto-negotiation.
 *       The supported speed and duplex modes are listed below
 *
 *       Bit           7     6     5      4      3     2     1      0
 *       Speed (Mbps)  N/A   N/A   1000   N/A    100   100   10     10
 *       Duplex                    Full          Full  Half  Full   Half
 *
 * @Default Value: 0x2F (copper)
 */
static int AutoNeg = OPTION_UNSET;
module_param(AutoNeg, int, 0);
MODULE_PARM_DESC(AutoNeg, "Advertised auto-negotiation setting");

#define PHY_ADVERTISE_10_HALF      0x0001
#define PHY_ADVERTISE_10_FULL      0x0002
#define PHY_ADVERTISE_100_HALF     0x0004
#define PHY_ADVERTISE_100_FULL     0x0008
#define PHY_ADVERTISE_1000_HALF    0x0010 /* Not used, just FYI */
#define PHY_ADVERTISE_1000_FULL    0x0020
#define PCH_AUTONEG_ADVERTISE_DEFAULT   0x2F

/**
 * FlowControl - User Specified Flow Control Override
 * @Valid Range: 0-3
 *    - 0:  No Flow Control
 *    - 1:  Rx only, respond to PAUSE frames but do not generate them
 *    - 2:  Tx only, generate PAUSE frames but ignore them on receive
 *    - 3:  Full Flow Control Support
 * @Default Value: Read flow control settings from the EEPROM
 */
static int FlowControl = OPTION_UNSET;
module_param(FlowControl, int, 0);
MODULE_PARM_DESC(FlowControl, "Flow Control setting");

/*
 * XsumRX - Receive Checksum Offload Enable/Disable
 * @Valid Range: 0, 1
 *    - 0:  disables all checksum offload
 *    - 1:  enables receive IP/TCP/UDP checksum offload
 * @Default Value: PCH_GBE_DEFAULT_RX_CSUM
 */
static int XsumRX = OPTION_UNSET;
module_param(XsumRX, int, 0);
MODULE_PARM_DESC(XsumRX, "Disable or enable Receive Checksum offload");

#define PCH_GBE_DEFAULT_RX_CSUM             true        /* trueorfalse */

/*
 * XsumTX - Transmit Checksum Offload Enable/Disable
 * @Valid Range: 0, 1
 *    - 0:  disables all checksum offload
 *    - 1:  enables transmit IP/TCP/UDP checksum offload
 * @Default Value: PCH_GBE_DEFAULT_TX_CSUM
 */
static int XsumTX = OPTION_UNSET;
module_param(XsumTX, int, 0);
MODULE_PARM_DESC(XsumTX, "Disable or enable Transmit Checksum offload");

#define PCH_GBE_DEFAULT_TX_CSUM             true        /* trueorfalse */

/**
 * pch_gbe_option - Force the MAC's flow control settings
 * @hw:             Pointer to the HW structure
 * Returns
 *      0:                      Successful.
 *      Negative value:         Failed.
 */
struct pch_gbe_option {
        enum { enable_option, range_option, list_option } type;
        char *name;
        char *err;
        int  def;
        union {
                struct { /* range_option info */
                        int min;
                        int max;
                } r;
                struct { /* list_option info */
                        int nr;
                        const struct pch_gbe_opt_list { int i; char *str; } *p;
                } l;
        } arg;
};

static const struct pch_gbe_opt_list speed_list[] = {
        { 0, "" },
        { SPEED_10, "" },
        { SPEED_100, "" },
        { SPEED_1000, "" }
};

static const struct pch_gbe_opt_list dplx_list[] = {
        { 0, "" },
        { HALF_DUPLEX, "" },
        { FULL_DUPLEX, "" }
};

static const struct pch_gbe_opt_list an_list[] =
        #define AA "AutoNeg advertising "
        {{ 0x01, AA "10/HD" },
         { 0x02, AA "10/FD" },
         { 0x03, AA "10/FD, 10/HD" },
         { 0x04, AA "100/HD" },
         { 0x05, AA "100/HD, 10/HD" },
         { 0x06, AA "100/HD, 10/FD" },
         { 0x07, AA "100/HD, 10/FD, 10/HD" },
         { 0x08, AA "100/FD" },
         { 0x09, AA "100/FD, 10/HD" },
         { 0x0a, AA "100/FD, 10/FD" },
         { 0x0b, AA "100/FD, 10/FD, 10/HD" },
         { 0x0c, AA "100/FD, 100/HD" },
         { 0x0d, AA "100/FD, 100/HD, 10/HD" },
         { 0x0e, AA "100/FD, 100/HD, 10/FD" },
         { 0x0f, AA "100/FD, 100/HD, 10/FD, 10/HD" },
         { 0x20, AA "1000/FD" },
         { 0x21, AA "1000/FD, 10/HD" },
         { 0x22, AA "1000/FD, 10/FD" },
         { 0x23, AA "1000/FD, 10/FD, 10/HD" },
         { 0x24, AA "1000/FD, 100/HD" },
         { 0x25, AA "1000/FD, 100/HD, 10/HD" },
         { 0x26, AA "1000/FD, 100/HD, 10/FD" },
         { 0x27, AA "1000/FD, 100/HD, 10/FD, 10/HD" },
         { 0x28, AA "1000/FD, 100/FD" },
         { 0x29, AA "1000/FD, 100/FD, 10/HD" },
         { 0x2a, AA "1000/FD, 100/FD, 10/FD" },
         { 0x2b, AA "1000/FD, 100/FD, 10/FD, 10/HD" },
         { 0x2c, AA "1000/FD, 100/FD, 100/HD" },
         { 0x2d, AA "1000/FD, 100/FD, 100/HD, 10/HD" },
         { 0x2e, AA "1000/FD, 100/FD, 100/HD, 10/FD" },
         { 0x2f, AA "1000/FD, 100/FD, 100/HD, 10/FD, 10/HD" }
};

static const struct pch_gbe_opt_list fc_list[] = {
        { PCH_GBE_FC_NONE, "Flow Control Disabled" },
        { PCH_GBE_FC_RX_PAUSE, "Flow Control Receive Only" },
        { PCH_GBE_FC_TX_PAUSE, "Flow Control Transmit Only" },
        { PCH_GBE_FC_FULL, "Flow Control Enabled" }
};

/**
 * pch_gbe_validate_option - Validate option
 * @value:    value
 * @opt:      option
 * @adapter:  Board private structure
 * Returns
 *      0:                      Successful.
 *      Negative value:         Failed.
 */
static int pch_gbe_validate_option(int *value,
                                    const struct pch_gbe_option *opt,
                                    struct pch_gbe_adapter *adapter)
{
        if (*value == OPTION_UNSET) {
                *value = opt->def;
                return 0;
        }

        switch (opt->type) {
        case enable_option:
                switch (*value) {
                case OPTION_ENABLED:
                        pr_debug("%s Enabled\n", opt->name);
                        return 0;
                case OPTION_DISABLED:
                        pr_debug("%s Disabled\n", opt->name);
                        return 0;
                }
                break;
        case range_option:
                if (*value >= opt->arg.r.min && *value <= opt->arg.r.max) {
                        pr_debug("%s set to %i\n", opt->name, *value);
                        return 0;
                }
                break;
        case list_option: {
                int i;
                const struct pch_gbe_opt_list *ent;

                for (i = 0; i < opt->arg.l.nr; i++) {
                        ent = &opt->arg.l.p[i];
                        if (*value == ent->i) {
                                if (ent->str[0] != '\0')
                                        pr_debug("%s\n", ent->str);
                                return 0;
                        }
                }
        }
                break;
        default:
                BUG();
        }

        pr_debug("Invalid %s value specified (%i) %s\n",
                 opt->name, *value, opt->err);
        *value = opt->def;
        return -1;
}

/**
 * pch_gbe_check_copper_options - Range Checking for Link Options, Copper Version
 * @adapter:  Board private structure
 */
static void pch_gbe_check_copper_options(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        int speed, dplx;

        { /* Speed */
                static const struct pch_gbe_option opt = {
                        .type = list_option,
                        .name = "Speed",
                        .err  = "parameter ignored",
                        .def  = 0,
                        .arg  = { .l = { .nr = (int)ARRAY_SIZE(speed_list),
                                         .p = speed_list } }
                };
                speed = Speed;
                pch_gbe_validate_option(&speed, &opt, adapter);
        }
        { /* Duplex */
                static const struct pch_gbe_option opt = {
                        .type = list_option,
                        .name = "Duplex",
                        .err  = "parameter ignored",
                        .def  = 0,
                        .arg  = { .l = { .nr = (int)ARRAY_SIZE(dplx_list),
                                         .p = dplx_list } }
                };
                dplx = Duplex;
                pch_gbe_validate_option(&dplx, &opt, adapter);
        }

        { /* Autoneg */
                static const struct pch_gbe_option opt = {
                        .type = list_option,
                        .name = "AutoNeg",
                        .err  = "parameter ignored",
                        .def  = PCH_AUTONEG_ADVERTISE_DEFAULT,
                        .arg  = { .l = { .nr = (int)ARRAY_SIZE(an_list),
                                         .p = an_list} }
                };
                if (speed || dplx) {
                        pr_debug("AutoNeg specified along with Speed or Duplex, AutoNeg parameter ignored\n");
                        hw->phy.autoneg_advertised = opt.def;
                } else {
                        int tmp = AutoNeg;

                        pch_gbe_validate_option(&tmp, &opt, adapter);
                        hw->phy.autoneg_advertised = tmp;
                }
        }

        switch (speed + dplx) {
        case 0:
                hw->mac.autoneg = hw->mac.fc_autoneg = 1;
                if ((speed || dplx))
                        pr_debug("Speed and duplex autonegotiation enabled\n");
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_HALF;
                break;
        case HALF_DUPLEX:
                pr_debug("Half Duplex specified without Speed\n");
                pr_debug("Using Autonegotiation at Half Duplex only\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 1;
                hw->phy.autoneg_advertised = PHY_ADVERTISE_10_HALF |
                                                PHY_ADVERTISE_100_HALF;
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_HALF;
                break;
        case FULL_DUPLEX:
                pr_debug("Full Duplex specified without Speed\n");
                pr_debug("Using Autonegotiation at Full Duplex only\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 1;
                hw->phy.autoneg_advertised = PHY_ADVERTISE_10_FULL |
                                                PHY_ADVERTISE_100_FULL |
                                                PHY_ADVERTISE_1000_FULL;
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_FULL;
                break;
        case SPEED_10:
                pr_debug("10 Mbps Speed specified without Duplex\n");
                pr_debug("Using Autonegotiation at 10 Mbps only\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 1;
                hw->phy.autoneg_advertised = PHY_ADVERTISE_10_HALF |
                                                PHY_ADVERTISE_10_FULL;
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_HALF;
                break;
        case SPEED_10 + HALF_DUPLEX:
                pr_debug("Forcing to 10 Mbps Half Duplex\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 0;
                hw->phy.autoneg_advertised = 0;
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_HALF;
                break;
        case SPEED_10 + FULL_DUPLEX:
                pr_debug("Forcing to 10 Mbps Full Duplex\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 0;
                hw->phy.autoneg_advertised = 0;
                hw->mac.link_speed = SPEED_10;
                hw->mac.link_duplex = DUPLEX_FULL;
                break;
        case SPEED_100:
                pr_debug("100 Mbps Speed specified without Duplex\n");
                pr_debug("Using Autonegotiation at 100 Mbps only\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 1;
                hw->phy.autoneg_advertised = PHY_ADVERTISE_100_HALF |
                                                PHY_ADVERTISE_100_FULL;
                hw->mac.link_speed = SPEED_100;
                hw->mac.link_duplex = DUPLEX_HALF;
                break;
        case SPEED_100 + HALF_DUPLEX:
                pr_debug("Forcing to 100 Mbps Half Duplex\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 0;
                hw->phy.autoneg_advertised = 0;
                hw->mac.link_speed = SPEED_100;
                hw->mac.link_duplex = DUPLEX_HALF;
                break;
        case SPEED_100 + FULL_DUPLEX:
                pr_debug("Forcing to 100 Mbps Full Duplex\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 0;
                hw->phy.autoneg_advertised = 0;
                hw->mac.link_speed = SPEED_100;
                hw->mac.link_duplex = DUPLEX_FULL;
                break;
        case SPEED_1000:
                pr_debug("1000 Mbps Speed specified without Duplex\n");
                goto full_duplex_only;
        case SPEED_1000 + HALF_DUPLEX:
                pr_debug("Half Duplex is not supported at 1000 Mbps\n");
                /* fall through */
        case SPEED_1000 + FULL_DUPLEX:
full_duplex_only:
                pr_debug("Using Autonegotiation at 1000 Mbps Full Duplex only\n");
                hw->mac.autoneg = hw->mac.fc_autoneg = 1;
                hw->phy.autoneg_advertised = PHY_ADVERTISE_1000_FULL;
                hw->mac.link_speed = SPEED_1000;
                hw->mac.link_duplex = DUPLEX_FULL;
                break;
        default:
                BUG();
        }
}

/**
 * pch_gbe_check_options - Range Checking for Command Line Parameters
 * @adapter:  Board private structure
 */
void pch_gbe_check_options(struct pch_gbe_adapter *adapter)
{
        struct pch_gbe_hw *hw = &adapter->hw;
        struct net_device *dev = adapter->netdev;
        int val;

        { /* Transmit Descriptor Count */
                static const struct pch_gbe_option opt = {
                        .type = range_option,
                        .name = "Transmit Descriptors",
                        .err  = "using default of "
                                __MODULE_STRING(PCH_GBE_DEFAULT_TXD),
                        .def  = PCH_GBE_DEFAULT_TXD,
                        .arg  = { .r = { .min = PCH_GBE_MIN_TXD,
                                         .max = PCH_GBE_MAX_TXD } }
                };
                struct pch_gbe_tx_ring *tx_ring = adapter->tx_ring;
                tx_ring->count = TxDescriptors;
                pch_gbe_validate_option(&tx_ring->count, &opt, adapter);
                tx_ring->count = roundup(tx_ring->count,
                                        PCH_GBE_TX_DESC_MULTIPLE);
        }
        { /* Receive Descriptor Count */
                static const struct pch_gbe_option opt = {
                        .type = range_option,
                        .name = "Receive Descriptors",
                        .err  = "using default of "
                                __MODULE_STRING(PCH_GBE_DEFAULT_RXD),
                        .def  = PCH_GBE_DEFAULT_RXD,
                        .arg  = { .r = { .min = PCH_GBE_MIN_RXD,
                                         .max = PCH_GBE_MAX_RXD } }
                };
                struct pch_gbe_rx_ring *rx_ring = adapter->rx_ring;
                rx_ring->count = RxDescriptors;
                pch_gbe_validate_option(&rx_ring->count, &opt, adapter);
                rx_ring->count = roundup(rx_ring->count,
                                PCH_GBE_RX_DESC_MULTIPLE);
        }
        { /* Checksum Offload Enable/Disable */
                static const struct pch_gbe_option opt = {
                        .type = enable_option,
                        .name = "Checksum Offload",
                        .err  = "defaulting to Enabled",
                        .def  = PCH_GBE_DEFAULT_RX_CSUM
                };
                val = XsumRX;
                pch_gbe_validate_option(&val, &opt, adapter);
                if (!val)
                        dev->features &= ~NETIF_F_RXCSUM;
        }
        { /* Checksum Offload Enable/Disable */
                static const struct pch_gbe_option opt = {
                        .type = enable_option,
                        .name = "Checksum Offload",
                        .err  = "defaulting to Enabled",
                        .def  = PCH_GBE_DEFAULT_TX_CSUM
                };
                val = XsumTX;
                pch_gbe_validate_option(&val, &opt, adapter);
                if (!val)
                        dev->features &= ~NETIF_F_ALL_CSUM;
        }
        { /* Flow Control */
                static const struct pch_gbe_option opt = {
                        .type = list_option,
                        .name = "Flow Control",
                        .err  = "reading default settings from EEPROM",
                        .def  = PCH_GBE_FC_DEFAULT,
                        .arg  = { .l = { .nr = (int)ARRAY_SIZE(fc_list),
                                         .p = fc_list } }
                };
                int tmp = FlowControl;

                pch_gbe_validate_option(&tmp, &opt, adapter);
                hw->mac.fc = tmp;
        }

        pch_gbe_check_copper_options(adapter);
}